Let's look now at another scale type that will expand your soloing variety. This scale will allow us to add some dramatic tension to our solos. However, it must be matched with the appropriate chord progressions in order to sound right. The minor scales come in three varieties: Natural Minor, Melodic minor, and Harmonic minor. Here we will discuss the Natural Minor Scale. You may recognize this scale as the Aeolian Mode from the previous discussion of modes.
Recall that we built the C Major Scale with a certain progression of steps: w-w-h-w-w-w-h. We will build our Natural Minor Scale in similar fashion, except now we will be altering the progression of steps. The formula for the Natural Minor Scale is w-h-w-w-h-w-w. Recognizing that the intervals for the major scale are 1-2-3-4-5-6-7-8, the intervals for the Natural Minor Scale will be 1-2-b3-4-5-b6-b7-8. Take notice of the flattened third, flattened sixth, and flattened seventh intervals. These are the intervals that give this scale its unique melancholy sound quality. Notice also that the Natural Minor Scale shares the flat third with the Minor Triad chord, and flat third and flat seventh intervals with the Minor Seventh chord, so this would be great scale to use over a Minor or Minor Seventh chord progression.
In order to bring out the intended sound of Natural Minor, when you solo using this scale you should emphasize the altered tones of the flat third, flat sixth, and flat seventh intervals.
You may have thought that these pattterns look similar to the Major Scale patterns except in a different order. If so, you are correct! The Natural Minor Scale bears a relationship to the Major Scale in that the root note of the Natural Minor Scale is the same note as the sixth interval of the corresponding Relative Major Scale. Conversely we could say that the sixth interval of a Major Scale is the root note of the Relative Minor Scale. For instance, in the key of C Major, the sixth interval is A. If you start on A and play through the notes from the key of C Major, you will be playing the same notes as the key of C Major. However, these same notes will also serve as the notes of A Natural Minor. The way you will distinguish the two scales is the notes which you resolve to, which will pull the sound of the scale toward the context established by your resolving notes. If you resolve to C notes, it will sound like C Major. If you resolve to A notes, then it will sound like A Natural Minor. More on the subject of the Relative Minor/Major later ...
In the mean time, practice these Natural Minor Scales by playing them over songs or backing tracks that use Minor sounding chord progressions.